Expanded – threaded – driven – headed – tool-deformed – or locked-thr – Externally threaded fastener element – e.g. – bolt – screw – etc. – Pilot end having means enhancing fastening or installation
Patent
1986-11-12
1988-03-15
Wilson, Neill
Expanded, threaded, driven, headed, tool-deformed, or locked-thr
Externally threaded fastener element, e.g., bolt, screw, etc.
Pilot end having means enhancing fastening or installation
411902, 411914, F16B 2500
Patent
active
047309709
ABSTRACT:
A process for making self-threading screw fasteners wherein only the cutting portions of the tip of the fasteners are hardened. The unhardened portions of the fastener remain ductile and are not subject to hydrogen embrittlement during subsequent plating to improve corrosion resistance. The process preferably comprises applying a radiation curable plastic coating over the drill tip followed by plating of a thin (minimum 0.0005 inch, 0.013 mm) layer of copper. The cured coating is then removed leaving an unplated tip. The screw is then subjected to a hardening process, wherein only the portions of the screw without the copper layer are hardened. The screw may then be plated conventionally with a corrosion resistant metal. The invention is further directed to the product of the process. A second embodiment for making screws suitable for extreme corrosion resistance is also described.
REFERENCES:
patent: 667555 (1901-02-01), McGahan
patent: 811573 (1905-05-01), Wallbank
patent: 1299232 (1919-04-01), Rosenberg
patent: 2712261 (1955-07-01), Anderson
patent: 3355205 (1967-11-01), Wagner et al.
patent: 3936366 (1976-02-01), Green
patent: 3948739 (1976-04-01), Chaudhari et al.
patent: 3989610 (1976-11-01), Tsukada et al.
patent: 4091137 (1978-05-01), Hage
patent: 4188459 (1980-02-01), Hyner
patent: 4203690 (1980-05-01), Tanaka et al.
patent: 4395173 (1983-07-01), Sygnator
Gradowski Steven
Hyner Jacob
Whyco Chromium Company
Wilson Neill
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